Independent dosing control system for washing machines

ABSTRACT

The invention relates to a method for controlling the dosing of detergent in multiple stage washing machines having at least one separate detergent tank per washing stage. The entry of water into a detergent tank of the washing machine releases, without intervention in the washing control system, the single dosing of a predetermined amount of detergent into the detergent tank, the release of further dosages being prevented until a renewed activation. Furthermore, the invention relates to a control device for dosing detergents in washing machines in accordance with one of the above methods.

BACKGROUND OF THE INVENTION

This invention relates to methods for controlling the dosing ofdetergents in multistage washing machines comprising at least onedispensing compartment and to a control system for carrying out suchmethods.

DISCUSSION OF RELATED ART

Multistage washing machines or those operating on the multibathprinciple carry out at least two of the following stages: prewash, mainwash, final wash, rinsing, softening, acidification, neutralization,disinfection, drying, and so forth. Some of these process stages requiredetergents or laundry aids which—in automatic washing machines—areautomatically dispensed into the machine. This generally involves onedispensing compartment per stage, the control system of the washingmachine ensuring that the water required to flush the detergent orlaundry aid into the machine is delivered to the particular dispensingcompartment.

Detergents or laundry aids can be formulated as powders, liquids orpastes. Automatic dosing systems for these products generally receivetheir control signals from the control system of the washing machine.This applies both to integrated systems and to separate systems whoseconnection generally entails modification of the washing machinecontrols. Such systems are complicated and—even if it takes allfunctions into consideration from the outset on an integrated basis—thehardware is very expensive.

Although the automation of the controls means that user-friendly systemsare available at falling prices, the subsequent installation of dosingsystems is complicated and expensive because of the necessarymodification of the electronic washing machine control system.

SUMMARY OF THE INVENTION

The technical problem addressed by the present invention is to develop adosing control system which works without any need for intervention inthe washing machine control system and which enables detergents to beautomatically dosed in a simple, uncomplicated manner. According to theinvention, the solution to this problem is a method for controlling thedosing to detergents of. The entry of water into a dispensingcompartment of the washing machine initiates the introduction of asingle predetermined dose of detergent into that dispensing compartmentwithout any need for intervention in the washing machine control system.The introduction of further doses remains blocked pending reactivation.A control system including a master sensor in at least one dispensingcompartment of the washing machine without connection to the washingmachine controls, is connected by a signal line to a dosing compartmentand, whenever water enters such a dispensing compartment equipped with amoisture sensor, a signal is generated and internally processed in thedosing control system, for initiating the introduction of apredetermined dose of detergent into that dispensing compartment.

A dosing control system of this type has the advantage that it can beinstalled very easily without intervention in the washing machine or thedosing system. A moisture sensor merely has to be provided in thosedispensing compartments for whose associated washing stage the automaticdosing of detergents or laundry aids is required. The signal generatedby the sensor on the entry of flushing water is relayed to the dosingcontrol system for the particular detergent. In order to ensure that adetergent is only dosed once per washing stage, the signal line isblocked after the first signal contact pending reactivation.

In one particular embodiment of the method according to the invention,which represents an extreme simplification, only the dosing system forthe second stage of a two-stage washing process is automated, the dosingsystem for the first stage being manually initiated with the beginningof the washing process. This manual initiation also reactivates theintroduction of a single dose for the second washing stage. In order tobe able advantageously to adapt the individual demand situation of theparticular washing process in a simple manner, at least a two-stagevolume controller is used in another variant of the method according tothe invention. A small/large volume can readily be selected for atwo-stage process or a small/medium/large volume for a three-stageprocess, depending on the particular demand of the laundry being washed.In one simple advantageous embodiment, the volume controller is manuallyadjusted.

The control system according to the invention for the dosing ofdetergents is so simple and uncomplicated that it can be installed oreven subsequently fitted using unskilled labor. The washing machinecontrol system—unaffected by this installation—ensures that flushingwater is introduced into the particular dispensing compartment beforethe next washing stage. When this flushing water wets the moisturesensor, the start signal is relayed to the dosing system and theparticular detergent is introduced into the dispensing compartment withthe wetted sensor. In the most simple case, the moisture sensor mayconsist of a single cable with two exposed terminals which generate asignal on wetting.

There is also no need for intervention in the dosing control systembecause only the start signal has to be delivered to the dosing systemand the dosing control system present in any case then triggers thenecessary measures. A preferred embodiment provides a device whichensures that only one dosing operation per washing stage is initiatedduring a cycle of the washing machine. Otherwise, dosing could bereactivated in a situation where the flushing water is introduced intothe dispensing compartment for longer than the time for which detergenthas to be dosed. The subject device may advantageously consist of anactivator which is designed to be connected to the signal line beforethe dosing system and which, after the first signal, interrupts the lineand can only be reactivated after the start of a new machine cycle.

A volume controller, for example with the settings small/large orsmall/medium/large, may also be designed as a separate module togetherwith the signal line. This volume controller is connected by the signalline to the dosing control system and can ensure the delivery of acorrespondingly predetermined quantity.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages described in the foregoing and other advantages willbecome clear from the following description of an embodiment of theinvention which is illustrated in the accompanying drawings, in whichlike items have the same reference designation, wherein:

FIG. 1 schematically illustrates the connection of dispensingcompartments of a washing machine to a separate dosing system.

FIG. 2 is a detailed schematic view of a dispensing compartment.

Although various embodiments of the invention have been shown anddescribed, they are not meant to be limiting. Those of skill in the artmay recognize certain modifications to those embodiments, whichmodifications are meant to be covered by the spirit and scope of theappended claims.

FIG. 1 schematically illustrates a washing machine 1 in which threedispensing compartments 2 for detergents or laundry aids are arranged atthe top right-hand front comer. The flushing water 5 is introducedthrough the nozzle 4 under the control of the washing machine controlsystem. The flushing water 5 wets the moisture sensor 7 which relays acorresponding signal through the signal line 8 to the signal input 11 ofthe dosing system 10. Associated with the signal input 11 is anactivator 13 which, after the first signal per wash cycle, interruptsthe signal line and is only reactivated with the beginning of a newmachine cycle.

The dosing system 10 controls the delivery of a corresponding dose ofdetergent through a dosing line 6 to the dose outlet 9 in the dispensingcompartment 2. This dose can be determined in advance by a volumecontroller 12. The detergent enters the dispensing compartment 2 and isflushed by the flushing water 5 coming from the nozzle 4 into the funnel3 and from there into the washing or treatment drum.

The volume controller 12 and activator 13 shown inside the dosing system10 in FIG. 1 may also be separately connected before the dosing system10 if these functions were not present from the outset in the dosingsystem 10.

The systematic arrangement of a dispensing compartment 2 shown in detailin FIG. 2 can be achieved in various ways. However, it must provide forthe basic functions described above. Thus, where several dispensingcompartments 2 are present, individual dosing lines 6 may run betweenthe connection of the dosing compartment and the dose outlet 9, as shownin the drawing. However, the individual connections may also be madethrough so-called manifolds and a common line positioned in between. Theflow directions for signals and media are indicated by arrows in thefeed line for the flushing water 5, the signal line 8 and the dosingline 6 and in the pipe disposed below the funnel 3.

What is claimed is:
 1. A method for controlling a dosing of detergentsin multistage washing machines comprising at least one dispensingcompartment, said method having steps including the entry of water intoa dispensing compartment of the washing machine initiating theintroduction of a single predetermined dose of detergent into thatdispensing compartment without any need for intervention in the washingmachine control system, wherein the predetermined dose of detergent isintroduced into the dispensing compartment and the introduction offurther doses is blocked pending reactivation.
 2. A method as claimed inclaim 1, wherein in a two-stage washing process, said method furtherincludes the steps of the dosing of detergent for the first stage beingmanually initiated with the beginning of the washing process, and thedosing of detergent for the second stage being initiated by the entry ofa water into the dispensing compartment for the second stage, whereby amanual start initiates reactivation.
 3. A method as claimed in claim 2,wherein the amount of detergent to be introduced per washing stage ispredetermined by at least a two-stage volume controller.
 4. A method asclaimed in claim 1, wherein the amount of detergent to be introduced perwashing stage is predetermined by at least a two-stage volumecontroller.
 5. A method as claimed in claim 4, wherein the volumecontroller is manually adjusted.
 6. A control system for dosingdetergents in washing machines comprising: a moisture sensor beingprovided in at least one dispensing compartment of the washing machineand, without connection to the washing machine controls, being connectedby a signal line to a dosing system and, whenever water enters adispensing compartment equipped with a moisture sensor, a signal beinggenerated and internally processed in the dosing control system,initiating the introduction of a predetermined dose of detergent intothat dispensing compartment wherein the dosing system is designed tointroduce a predetermined dose of detergent into the dispensingcompartment; and a device which only allows one dosing operation perwashing stage during a cycle of the washing machine consisting of anactivator for interrupting the signal line after the first signal.
 7. Acontrol system as claimed in claim 6, wherein said device consists of anactivator for interrupting the signal line after the first signal whichcan only be reactivated with the beginning of a new washing machinecycle.
 8. A control system as claimed in claim 7, further including atleast a two-stage volume controller which predetermines the size of thedetergent dose for a washing stage, the volume controller preferablybeing manually adjustable.
 9. A control system as claimed in claim 6,further including at least a two-stage volume controller whichpredetermines the size of the detergent dose for a washing stage, thevolume controller preferably being manually adjustable.
 10. A controlsystem as claimed in claim 6, further including at least a two-stagevolume controller with predetermines the size of the detergent dose fora washing stage, the volume controller preferably being manuallyadjustable.